{"api_version":"1","generated_at":"2026-09-01T06:22:45+00:00","cve":"CVE-2026-19873","urls":{"html":"https://cve.report/CVE-2026-19873","api":"https://cve.report/api/cve/CVE-2026-19873.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-19873","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-19873"},"summary":{"title":"HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements","description":"HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements.\n\nWhen a Repeatable element has counter_name set, its process method reads the repeat count from the named query string parameter, checks only that it is a positive integer, and passes it to repeat, which deep-clones the element's child subtree once per iteration. Nothing caps the value, and no attribute lets an application impose a limit.\n\nThe count is read on every request, before the form decides whether it was submitted, so a plain GET reaches the clone loop with no credentials, no session and no request body. Nesting multiplies: a Repeatable inside a Repeatable takes a counter at each level, so an outer and an inner value of 100 build 10,000 clones.\n\nOnce the form is submitted, each cloned field's constraints scan the whole element tree in _find_field_value, so cost grows faster than linearly with the count. A single request exhausts memory and CPU.\n\nThe latest release on CPAN is 2.07, from 2018. Version 2.08 exists only in the git repository.","state":"PUBLISHED","assigner":"CPANSec","published_at":"2026-08-31 10:16:49","updated_at":"2026-08-31 18:17:14"},"problem_types":["CWE-770","CWE-1284","CWE-1284 CWE-1284 Improper Validation of Specified Quantity in Input","CWE-770 CWE-770 Allocation of Resources Without Limits or Throttling"],"metrics":[{"version":"3.1","source":"ADP","type":"DECLARED","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}},{"version":"3.1","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://security.metacpan.org/patches/H/HTML-FormFu/2.08/CVE-2026-19873-r1.patch","name":"https://security.metacpan.org/patches/H/HTML-FormFu/2.08/CVE-2026-19873-r1.patch","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"http://www.openwall.com/lists/oss-security/2026/08/31/7","name":"http://www.openwall.com/lists/oss-security/2026/08/31/7","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/FormFu/HTML-FormFu/issues/71","name":"https://github.com/FormFu/HTML-FormFu/issues/71","refsource":"9b29abf9-4ab0-4765-b253-1875cd9b441e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-19873","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-19873","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[{"source":"CNA","title":"","value":"Apply the patch. 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Where the client-side repeat feature is not needed, unsetting counter_name stops the count being read from the query string.","time":"","lang":"en"}],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"providerMetadata":{"dateUpdated":"2026-08-31T12:11:31.961Z","orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE"},"references":[{"url":"http://www.openwall.com/lists/oss-security/2026/08/31/7"}],"title":"CVE Program Container"},{"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}},{"other":{"content":{"id":"CVE-2026-19873","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","timestamp":"2026-08-31T17:56:55.337977Z","version":"2.0.3"},"type":"ssvc"}}],"providerMetadata":{"dateUpdated":"2026-08-31T17:57:13.999Z","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP"},"title":"CISA ADP Vulnrichment"}],"cna":{"affected":[{"collectionURL":"https://cpan.org/modules","defaultStatus":"unaffected","modules":["HTML::FormFu"],"packageName":"HTML-FormFu","packageURL":"pkg:cpan/HTML-FormFu","programFiles":["lib/HTML/FormFu/Element/Repeatable.pm","lib/HTML/FormFu/Constraint.pm"],"programRoutines":[{"name":"HTML::FormFu::Element::Repeatable::process"},{"name":"HTML::FormFu::Element::Repeatable::repeat"},{"name":"HTML::FormFu::Constraint::_find_field_value"}],"repo":"https://github.com/FormFu/HTML-FormFu","versions":[{"lessThanOrEqual":"2.08","status":"affected","version":"0","versionType":"custom"}]}],"descriptions":[{"lang":"en","value":"HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements.\n\nWhen a Repeatable element has counter_name set, its process method reads the repeat count from the named query string parameter, checks only that it is a positive integer, and passes it to repeat, which deep-clones the element's child subtree once per iteration. 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There is no fixed release."}],"source":{"discovery":"UNKNOWN"},"title":"HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements","workarounds":[{"lang":"en","value":"For deployments that cannot apply the patch, reject or clamp the counter parameter before passing the query to process. Where the client-side repeat feature is not needed, unsetting counter_name stops the count being read from the query string."}],"x_generator":{"engine":"cpansec-cna-tool 0.1"}}},"cveMetadata":{"assignerOrgId":"9b29abf9-4ab0-4765-b253-1875cd9b441e","assignerShortName":"CPANSec","cveId":"CVE-2026-19873","datePublished":"2026-08-31T10:07:32.134Z","dateReserved":"2026-08-14T12:57:36.382Z","dateUpdated":"2026-08-31T17:57:13.999Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-31 10:16:49","lastModifiedDate":"2026-08-31 18:17:14","problem_types":["CWE-770","CWE-1284","CWE-1284 CWE-1284 Improper Validation of Specified Quantity in Input","CWE-770 CWE-770 Allocation of Resources Without Limits or Throttling"],"metrics":{"cvssMetricV31":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-08-31T17:56:55.337977Z","id":"CVE-2026-19873","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"19873","Ordinal":"1","Title":"HTML::FormFu versions through 2.08 for Perl allow resource exhau","CVE":"CVE-2026-19873","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"19873","Ordinal":"1","NoteData":"HTML::FormFu versions through 2.08 for Perl allow resource exhaustion via an unbounded repeat count from the query string in Repeatable elements.\n\nWhen a Repeatable element has counter_name set, its process method reads the repeat count from the named query string parameter, checks only that it is a positive integer, and passes it to repeat, which deep-clones the element's child subtree once per iteration. 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